PNL’s neutron generator technology utilizes the DD and DT nuclear fusion reactions to generate neutrons. There are many commercially available DD and DT neutron generators but most of them operate solid targets that limit the lifetime and neutron yield of these devices. Furthermore, common COTS solutions employ ion sources that fundamentally limit the amount of beam current that can be accelerated for neutron production.
PNL’s solution utilizes a microwave ion source (MWS) and a gaseous deuterium, tritium, or mixed species target, which allows for a significantly increased neutron yield, as well as longer target and source lifetimes for up to several years. A high voltage DC power supply that was designed internally at PNL, brings the entire top sheet, and all electronics on it, to a potential of 300 kV. A magnetron produces microwaves that are guided into a plasma chamber filled with deuterium gas. An 875 Gauss magnetic field is generated within the plasma chamber, and the interaction of the 2.45 GHz microwaves in the presence of the specific magnetic field configuration, causes the gas to be ionized in a very efficient manner. D+ ions are then extracted from the plasma chamber and accelerated to 300 kV by a direct-inject, CW accelerator. The beam is then focused by a magnetic solenoid and transported down a beam line with several stages of differential pumping, until it impinges upon a target chamber filled with deuterium and/or tritium gas, where nuclear fusion occurs and then neutrons are produced.
A schematic and image of the PNL neutron generator is shown below: